Continuous sheet slitting mills

ABSTRACT

In a mill for slitting wide sheets a tensioning device is provided for simultaneously braking, without any friction effect, a plurality of strips to be subsequently reeled on a same coiling drum, wherein the necessary braking effort is transmitted to endless belts, the braking means are adapted to impart different speeds to said endless belts which are equal to the speeds of the cut strips to be braked, respectively.

United States Patent 1191 Plantard 1 May 29, 1973 [54] CONTINUOUS SHEET SLITTING 3,468,494 9 1969 Gaudin ..242 75.2 MILLS 3,547,332 12/1970 .....242/7s.2 2,961,183 11/1960 .....242/75.2 Inventor: Bernard Plantard, rue du (3198- 2,393,322 4/1946 Faris ..242/7s.2

' des Moines 95, Argenteuil, France Prima Examiner-Geor e F. Mautz F 1 1 r b. 1 g [22] 1 ed e 197 Assistant Examiner-Edward J. McCarthy [21] Appl. No.: 113,304 AttorneyDavis,'1-1oxie, Faithfu1l& Hapgood [52] Cl. ..242/75.2, 226/195, 242/562 [57] ABSTRACT 51 int. Cl ..B65h 23/10, B65h 23/30 In a mill for slitting Wide Sheets a tensioning device is [58 Field 61 Search ..242/75.2, 56.2, 75.4, Provided for Simultaneously braking, without y fric- 242/75 75A 15 1 156 67 1 R, 672 I101! effect, a plurality Of strips to be subsequently 673 226/39 195 reeled on a same coiling drum, wherein the necessary braking effort is transmitted to endless belts, the braking means are adapted to impart different speeds to [56] References Cited said endless belts which are equal to the speeds of the UNITED STATES PATENTS cut strips to be braked, respectively. 2,399,155 4/1946 Reed ..242/75.1 X 21 Claims, 9 Drawing Figures Patented May 29, 1973 3 Sheets-Sheet 1 Patented May 29, 1973 3,735,937

5 Sheets-Sheet 5 I /0 1 I I a i 1 L5 if i Z Ll 1 CONTINUOUS SHEET SLI'I'IING MILLS The present invention relates to continuous sheet slitting mills and has specific reference to a device capable of producing a counter-traction uniformly distributed to a plurality of strips to be reeled on a common coiling drum.

The commonest application of this device is contemplated for reeling strips delivered from a slitting mill.

Cutting or slitting relatively wide sheets, generally of metallic material, consists in cutting the coiled sheet in r the longitudinal direction; otherwise stated, an initially wide sheet of relatively great length is reduced into sheets of same length but relatively small width.

A conventional slitting installation comprises as a rule, as illustrated in FIG. 1 of the attached drawings:

a coil of sheet 1,

a deflector 2,

a multiple-cutter shearing device 3, and

a coiling reel 4.

It will be noted that the fact of cutting a relatively wide sheet in the longitudinal direction makes it hardly possible to deliver strips having the same tension to the coiling reel, due to unavoidable differences in thickness between the center and the edges of the strip, or on account of internal stress existing in the strip released as a consequence of the cutting operation. On the other hand, during the winding or coiling operation each one of the individual coils thus formed must be kept somewhat spaced from the adjacent coil or coils by suitable mechanical means in order to avoid any overlapping of adjacent strips. If the strips are separated while a certain tension is exerted thereon, damage is generally observed on the edges of the slit strips.

Now it is the essential object of this invention to avoid the difficulties mentioned hereinabove and permit the coiling of uniformly compact strip coils without any mutual engagement of their adjacent edges.

On the other hand, it is very important to avoid any damage to the surface of the products utilized in a slitting mill. Although a simple press disposed before the reeler for example in the case of hot-roller steels can be used, this technique is definitely precluded in the case of:

cold-rolled steels having a fragile surface structure;

all painted or enamelled metals,

all bright stainless products,

aluminum, light-alloys, etc.

The device of this invention is utilized necessarily in a mill of the so-called loop type having a kinematic arrangement well known in the art, that is, wherein the shearing device delivers the cut strips into a pit before they are directed to the reeling means. The chief object of this technique is to separate the strips while they are still slack as they emerge from the pit. This separation is accomplished by a straight or rotary separator constituting a known assembly designated by the reference numeral 5 in FIG. 1.

Between this separator 5 and the coiling drum 4 the device according to this invention, constituting an advantageous substitute for various known means, of which the simplest one is the shoe press, is disposed. This device illustrated diagrammatically in FIG. 1 is designated in general by the reference numeral 6.

This device 6 comprises a plurality of endless belts to which the braking effort is transmitted, and is characterized in that it incorporates braking means permitting different speeds of these belts which are equal respectively to the speeds of the slit strips to be braked.

According to a specific feature of this invention said endless belts are passed over pulleys braked individually and disposed in staggered relationship in order to guide the belts by and along their edges.

According to another feature characterizing this invention the endless belts are caused to bear on the strips by means of rows of rollers urged away from the frame structure of the device by means of inflatable elasfic bladders, said. belts being furthermore guided laterally by other rollers of relatively small diameter supported by said frame structure.

According to this invention the means provided for braking the pulleys over which the belts are passed consist of a plurality of members each interposed between adjacent pulleys of a pair and axially movable on the distance-pieces of the pulley bearings but held against rotation by said distance-pieces, each member aforesaid being hollowed for receiving an expansible hollow toroidal bladder or like element adapted to be inflated like the inner tube of a tyre with compressed air in order to press friction linings or washers associated with each pulley against the pulleys between which said inflatable bladder is disposed.

According to a further feature characterizing this invention each member adapted to brake the pulleys comprises a pair of friction linings, one lining being glued or riveted to one lateral face of the member and the other, of greater thickness, being fitted in the cavity.

of said hollow member with a clearance sufficient to permit the axial movement of said other lining.

According to this invention the belt pressing rollers consist of a plurality of rolling-contact bearings stacked on a common shaft secured by suitable support members to a plate receiving the thrust from said inflatable elastic bladder.

According to a modified form of embodiment of this invention the braking effort is applied directly to the belts proper, at the points where the belts are clamped to the strips. In this case compound belts consisting of two materials are used: the first material engaging the strips consists of an elastomer having good mechanical properties and a relatively high coefficientof friction, and the other material is a relatively thin metal strip. The two sheets constituting each compound belt are pressed against the strips by means of plates urged away from the frame structure of the device by inflatable elastic bladders. Other features and advantages of this invention will appear as the following description proceeds with reference to the accompanying drawings illustrating diagrammatically by way of example a few typical forms of embodiments thereof.

In the drawings: a FIG. 1 illustrates the general arrangement of a slitting mill already broadly described in the above preamble and incorporating the tensioning device 6 constituting the subject-matter of this invention;

FIG. 2 shows on a larger scale and in diagrammatic side-elevational view the essential component elements of this device;

FIG. 3 is a cross-sectional view of a detaihshown on a still larger scale;

FIG. 4 illustrates the mounting of the belt bearing rollers;

FIG. 5, 6 and 7 are diagrams illustrating the possible positions of the device of this invention in a slitting mill;

FIG. 8 illustrates diagrammatically a modified form of embodiment of the invention, and

FIG. 9 is a section taken along the plane A-A of FIG. 8 on a considerably enlarged scale.

Referring to FIG. 2 it will be seen that the strips 2b are caused to pass through a set of clamping belts 2c, then deflected by a roll 2d before they are coiled on the drum 4. The belts 2c consist of a plurality of relatively narrow elements, their width ranging from about to about 50 mm according to requirements, for a same sheet. These belts pass over pulleys 2e braked separately by means to be described presently. These belts are caused to bear against the strips by a row of rollers 2f urged away from the frame structure 2g of the device by inflatable elastic bladders 2h. In order to obtain a satisfactory coiling of the strips the belts must be guided laterally by rollers 2i of relatively small diameter supported by the frame structure of the device.

The pulleys 2e are disposed in staggered relationship. This arrangement ensures a proper guiding of the belts by and along their edges. In addition, it permits the exertion of an individual braking effort on the pulleys, as will be described hereinafter.

Finally, a deflector roll 2d mounted for loose rotation and having its axial shaft rigid with the frame structure of the device bears without any appreciable pressure against the coiling drum 4. This roll 2d over which the strips are caused to pass at different linear speeds at the end of the separating phase and before the coiling phase must necessarily have a chrome-plated, highly polished surface to prevent on the one hand the scratching of fragile materials and on the other hand the driving by adherence of the strips travelling at the lowest speed. However, this roll 2d may also consist of several independant sections.

FIG. 3 illustrates in section the mounting of pulleys 2e. Now these pulleys must be braked separately since their rotational speeds may differ from one another.

As already mentioned hereinabove these pulleys 2e are disposed in staggered relationship and between adjacent pulleys a gap corresponding to the thickness of one pulley is provided for receiving the braking means. This brake is extremely simple and consists essentially of a member 30 disposed between two adjacent pulleys 2e; this member 3a is axially movable on, but held against rotation by the bearing distance-pieces 3c. Said member 3a is furthermore hollowed on one lateral face for accomodating an expansible toroidal bladder 3f of suitable elastic plastic material adapted to be inflated with compressed air delivered through a supply pipe 3d. As a consequence of this inflation, friction linings 3e associated with each brake are pressed against the adjacent pulleys 2e. One lining is secured to the member 3a by gluing or riveting and the other, thicker lining is fitted into the opposite lateral cavity of member 3a with a clearance permitting its axial movement therein. Thus by properly adjusting the pneumatic pressure in pipe 3d the braking effort applied to the pulleys may be adjusted at will.

The endless belts pass over the pulleys 2e, as shown. These belts may be flat or V-sectioned and must have essentially the following properties:

a. their surface must have a good coefficient of friction, without producing any abrasive effect,

b. within practical limits, they should not become unduly elongated during their useful life, in order to avoid with weight and dimensional requirements of the device it is desirable that these rollers have a relatively reduced diameter so that their shaft 4b must also have a relatively small diameter. This shaft 4b is supported by relatively thin plates 40 interposed between pairs of adjacent bearings. These supporting plates 4c are rigid with a base plate 4d receiving the thrust produced by the inflation of the inflatable bladder 2h provided for moving the row of rollers from the frame structure 23 (see FIG. 2).

To ensure a satisfactory adherence of all the rollers to the belts 2c it is also desirable that the base plate 4d be relatively thin so that it can yield slightly under the pressure of said bladder 2h and thus cause the rollers to bear with a substantially uniform pressure against the belts. The bladder 2h consists of a piece of deformable plastic material adapted to withstand a relatively low air pressure. Of course, the base plate 4d will be held against movement with respect to the strip.

Now reference will be made to a modified form of embodiment shown in FIGS. 8 and 9, wherein the belts are adapted to be retarded or braked without acting upon the deflection pulleys. To this end the friction effort is applied directly to the belts across the points of clamping contact between the belts and the strips.

An essential requirement to be met for carrying out this modified form of embodiment is that the force causing the mutual adherence of the belts and strips exceeds the frictional contact between the belts and the means provided for producing their clamping action. In fact, any slip between the belts and strips must be positively avoided for otherwise the device would operate as a simple press and display the inconveniences described hereinafter.

In this modified form of embodiment the strips 10 are caused to move between the two sheets of belts l2. According to this invention the belts 12 are of the compound type, i.e. consist of two mutually adhering layers or sheets of different materials 11 and 15. The inner material 15 contacting the strips 10 consists preferably of an elastomer having good mechanical properties and a very satisfactory coefiicient of friction; thus, polyurethane may be used to this end. Its hardness will be sufficiently moderate to avoid the impression of its surface flaws or defect into the strip coating or surface. The other material 11 consists of relatively thin metal having a highly-polished surface on the face contacting the clamping plate 13 (to be described hereinafter); thus, stainless steel may be used to this end. The two layers of materials 11, 15 adhere to each other and on the other hand their outer surfaces must have a good adherence. To this end, a convenient compound belt may be obtained by moulding a polyurethane layer on steel. To permit the pressing of belts 12 against the strips 10, the belts 12 are supported by plates 13 receiving the clamping force of a pair of inflatable bladders 16 similar to the bladders 2h described hereinabove with reference to FIG. 2. Necessarily, the plate surfaces engaging the metal face of belts 12 must have a good coefficient of friction and have self-lubricating properties; thus, sintered metal plates or Teflon-coated steel bands may be used.

In order to dissipate the heat developed by the braking action exerted by the belts on the strips, this selflubricating portion will be solid with a material having a good heat conductibility.

In the example illustrated (FIG. 9) the clamping plates 13 constitute the wallsof hollow bodies 14 and a suitable cooling fluid is circulated through the cavities of these bodies.

In FIGS. 5, 6 and 7 the different positions in which the device according to this invention can be mounted in a slitting mill are illustrated.

FIG. .5 illustrates the device 6 mounted on a pivoting shaft 7 overlying the coiling drum 4.

FIG. 6 illustrates the pivoting of the complete frame structure of the device 6 about an axis 8 disposed be tween the loop and the coiling device 4, and FIG. 7 illustrates a modified arrangement wherein the device 6 is adapted to be moved parallel to the mill axis.

This last arrangement is particularly advantageous in that it permits of directing the leading ends of the strip between the shearing device and the coiling device. In fact, it is possible to control the rotation of the set of pulleys 2e for example by means of a small pneumatic motor when the braking of these pulleys is given. To this end it is only necessary to control the rotation of shaft 3h. Under these conditions a contrary effect, i.e. a driving of the strips, is obtained. If the device is placed in position I and the belts are actuated when the strips are fed to the device, these strips will proceed naturally through the device. Under these conditions it is only necessary to transfer the complete device as a unit from position I to position II and to restart the belts so that the strips proceed to the coiling drum 4. This arrangement is particularly advantageous for in most cases the relative spacing of the shearing device and coiling device is in excess of 5 meters. In the case of thin and narrow materials substantial losses of time are experienced and therefore with the present invention the efficiency of the mill is improved considerably.

What is claimed is:

1. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts disposed on each side of said plurality of strips for engaging said plurality of strips therebetween and means for individually braking said belts to permit different speeds of said belts, said speeds being respectively equal to those of the adjacent slit strips to be braked.

2. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween, said endless belts being passed over pulleys braked independently of one another to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, said pulleys being disposed in staggered relationship in order to permit the guiding of said belts along their edges.

3. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a frame structure, a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts to permit diflerent speeds of said belts respectively equal to the speeds of the strips to be braked, said belts being pressed against said strips by rows of rollers urged away from the frame structure of the device by means of inflatable elastic bladders, said belts being furthermore guided laterally by rollers of relatively small diameter supported by said frame structure.

4. Mill according to claim 2, characterized in that the means provided for braking said pulleys engaged by said belts comprise members each interposed between the adjacent pulleys of a pair and axially movable on the distance-pieces of the pulley bearings but held against rotation by said distance-pieces, each member being hollowed for receiving an expansible toroidal bladder adapted to be inflated with compressed air for pressing friction linings provided on said members against the pulleys between which said member is disposed.

5. Mill according to claim 4, characterized in that each one of the members provided for braking said pulleys independently comprises two friction linings, one relatively thin secured by gluing or riveting to one lateral face of said member and the other relatively thick fitted withclearance in the cavity of said member so as to be axially movable therein.

6. Mill according to claim 4, characterized in that said toroidal bladder is supplied with compressed air from a suitable generator, the air pressure being adjusted for varying the braking pressure value at will.

7. Millaccording to claim 3, characterized in that said belt pressing rollers are divided in the axial direction into a plurality of narrow rollers of a width not in excess of the belt width.

8. Mill according to claim 7, characterized in that said presser rollers consist of rolling-contact bearings stacked on a common shaft mounted to supporting plates rigid with a base plate receiving the thrust from said inflatable elastic bladder for holding said rows of rollers away from the frame structure of the device.

9. Mill according to claim 1, characterized in that it comprises a deflector roll mounted for loose rotation on a shaft rigid with the frame structure of the device,

said deflector roll bearing without any appreciable pressure on the coiling drum on which the slit strips are to be wound, said deflector roll being chrome-plated and comprising preferably a plurality ofaxial sections.

10. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, the tension device braking the strips being mounted on a shaft pivoting above the drum on which the slit strips are wound.

11. Mill according to claim 1, characterized in that the tension device for braking the strips is pivotally mounted about a shaft disposed between loops formed by the strips after the shearing of the sheet and the coiling drum.

12. Mill according to claim 1, characterized in that said device is movable parallel to the mill axis.

13. Mill according to claim 1, characterized in that the braking effort is applied directly to the belts themselves across the points where said belts engage said strips.

14. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts by applying braking effort directly to the belts across the points where said belts engage said strips to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, said belts being of the compound type comprising two layers of different materials, namely a first layer contacting said strip and consisting preferably of an elastomer having good mechanical properties and a very satisfactory coefficient of friction, and a second relatively thin layer of a suitable metal, the two layers of the belt being pressed against the strips by clamping plates urged away from the frame structure of the device by inflatable elastic bladders.

15. Mill according to claim 14, characterized in that the aforesaid second layer of material engaging the clamping plate is highly polished.

16. Mill according to claim 14, characterized in that said first material consists of polyurethane and the second material consists of stainless steel, said polyurethane layer being welded to the steel surface.

17. Mill according to claim 14, characterized in that the surfaces of said clamping plates engaging the metal layer of said belts are self-lubricating and have a good coefl'icient of friction.

18. Mill according to claim 17, characterized in that said surfaces of said clamping plates consist of sintered metal plates or Teflon-coated steel bands.

19. Mill according to claim 17, characterized in that said self-lubricating portion is solid with a material having a good heat conductibility.

20. Mill according to claim 14, characterized in that said clamping plates constitute the walls of hollow bodies and that a suitable cooling fluid is circulated in the cavities of said bodies.

21. Mill according to claim 4 characterized in that said device comprises means for rotating said distancepieces to rotate the complete set of pulleys over which said belts are passed. 

1. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts disposed on each side of said plurality of strips for engaging said plurality of strips therebetween and means for individually braking said belts to permit different speeds of said belts, said speeds being respectively equal to those of the adjacent slit strips to be braked.
 2. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween, said endless belts being passed over pulleys braked independently of one another to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, said pulleys being disposed in staggered relationship in order to permit the guiding of said belts along their edges.
 3. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a frame structure, a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, said belts being pressed against said strips by rows of rollers urged away from the frame structure of the device by means of inflatable elastic bladders, said belts being furthermore guided laterally by rollers of relatively small diameter supported by said frame structure.
 4. Mill according to claim 2, characterized in that the means provided for braking said pulleys engaged by said belts comprise members each interposed between the adjacent pulleys of a pair and axially movable on the distance-pieces of the pulley bearings but held against rotation by said distance-pieces, each member being hollowed for receiving an expansible toroidal bladder adapted to be inflated with compressed air for pressing friction linings provided on said members against the pulleys between which said member is disposed.
 5. Mill according to claim 4, characterized in that each one of the members provided for braking said pulleys independently comprises two friction linings, one relatively thin seCured by gluing or riveting to one lateral face of said member and the other relatively thick fitted with clearance in the cavity of said member so as to be axially movable therein.
 6. Mill according to claim 4, characterized in that said toroidal bladder is supplied with compressed air from a suitable generator, the air pressure being adjusted for varying the braking pressure value at will.
 7. Mill according to claim 3, characterized in that said belt pressing rollers are divided in the axial direction into a plurality of narrow rollers of a width not in excess of the belt width.
 8. Mill according to claim 7, characterized in that said presser rollers consist of rolling-contact bearings stacked on a common shaft mounted to supporting plates rigid with a base plate receiving the thrust from said inflatable elastic bladder for holding said rows of rollers away from the frame structure of the device.
 9. Mill according to claim 1, characterized in that it comprises a deflector roll mounted for loose rotation on a shaft rigid with the frame structure of the device, said deflector roll bearing without any appreciable pressure on the coiling drum on which the slit strips are to be wound, said deflector roll being chrome-plated and comprising preferably a plurality of axial sections.
 10. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, the tension device braking the strips being mounted on a shaft pivoting above the drum on which the slit strips are wound.
 11. Mill according to claim 1, characterized in that the tension device for braking the strips is pivotally mounted about a shaft disposed between loops formed by the strips after the shearing of the sheet and the coiling drum.
 12. Mill according to claim 1, characterized in that said device is movable parallel to the mill axis.
 13. Mill according to claim 1, characterized in that the braking effort is applied directly to the belts themselves across the points where said belts engage said strips.
 14. Sheet slitting mill including a tension device for braking simultaneously and without any friction a plurality of strips delivered to a common coiling drum, characterized in that said device comprises a plurality of endless belts for engaging said plurality of strips therebetween and means for individually braking said belts by applying braking effort directly to the belts across the points where said belts engage said strips to permit different speeds of said belts respectively equal to the speeds of the strips to be braked, said belts being of the compound type comprising two layers of different materials, namely a first layer contacting said strip and consisting preferably of an elastomer having good mechanical properties and a very satisfactory coefficient of friction, and a second relatively thin layer of a suitable metal, the two layers of the belt being pressed against the strips by clamping plates urged away from the frame structure of the device by inflatable elastic bladders.
 15. Mill according to claim 14, characterized in that the aforesaid second layer of material engaging the clamping plate is highly polished.
 16. Mill according to claim 14, characterized in that said first material consists of polyurethane and the second material consists of stainless steel, said polyurethane layer being welded to the steel surface.
 17. Mill according to claim 14, characterized in that the surfaces of said clamping plates engaging the metal layer of said belts are self-lubricating and have a good coefficient of friction.
 18. Mill according to claim 17, characterized in that said surfaces of said clamping plates consist of sintered Metal plates or Teflon-coated steel bands.
 19. Mill according to claim 17, characterized in that said self-lubricating portion is solid with a material having a good heat conductibility.
 20. Mill according to claim 14, characterized in that said clamping plates constitute the walls of hollow bodies and that a suitable cooling fluid is circulated in the cavities of said bodies.
 21. Mill according to claim 4 characterized in that said device comprises means for rotating said distance-pieces to rotate the complete set of pulleys over which said belts are passed. 